


Dreamswap Underverse

by WyvrnaKindSoul



Category: Undertale, Underverse - Fandom, dreamswap - Fandom
Genre: Gen, Mention of DS Dream, XTale
Language: English
Status: In-Progress
Published: 2019-03-02
Updated: 2019-03-01
Packaged: 2019-11-07 19:08:13
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 1,941
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17966333
Author URL: https://archiveofourown.org/users/WyvrnaKindSoul/pseuds/WyvrnaKindSoul
Summary: Nightmare meets a "new friend" out in the multiverse. He and his "new friend" interact.





	1. New Friend

Nightmare drifted around from AU to AU aimlessly, trying to find people his stupid-tall-as-fuck-winged brother wanted to kill for the very bullshit reason he even exists. He shook it off, trying to focus on staying off the grid from Dream’s organization.

He had to admit, seeing the different islands for every AU out there was interesting. Although he didn’t approve of the slow travel, but his brothers organization wasn’t able to travel like this to his knowledge and he enjoyed seeing more AUs he more he explored and escaped from Dream.

He sat on the edge of an island for an Underfell, skimming through to see what AU he could travel to next. It was hard to find a safe place to just relax ever since Dream set out to kill him, he couldn’t stay around the islands for long anyways. They could find him faster if they sensed him out on the islands.

He sighed, his purple cape billowing in the red winds of the island and trying to search for anyone Dream may try to kill. “Damn bastard.” He muttered.

Nightmare’s head suddenly perked up, sensing energy much larger than that of his brother’s aura. He stood up, hopping through each island to find the source. Following the source made him take larger leaps as the islands became more spread out.

He suddenly tripped, falling under one of the islands and grabbing hold of a root. Nightmare’s breath quickened, he had no idea what was under all of these islands, but he didn’t want to find out. He climbed up the roots with all his might, just reaching the top when the final root snapped and sent him falling.

“Shit!” He tried to grab onto another root, but the force broke the one he grabbed on.

_This is it. This is how I fucking die._ Nightmare thought frantically, unable to think of any way to save himself.

Just as when he thought he would die or fall forever, he landed on a tree, tumbling down onto grass.

Nightmare got up, finding himself on the base of an achromatic island, purple and yellow flowers with two or three white trees scattered around a door with no name. Cracks grew around the door and island, and the source along with strong negative feelings came from inside this AU.

_Why is this place so far from the others?_ Nightmare thought, looking at the still breaking door. This AU, whatever its name is, was trying to destroy itself.

_Not on my watch._ Nightmare opened the door, purple waves of light pouring out as he entered.

He found himself in a white field with yellow flowers. The sky was even achromatic as well.

“So weird,” Nightmare commented, “This place seems totally empty, but I can feel this place self-destructing.”

He heard giggling behind him. Nightmare turned to see two children, one with dark grey hair and a white shirt and black pants, holding a bunch-full of yellow flowers, being chased by a white haired child with the same clothing but with a white long cape with a black outline.

They stopped in front of Nightmare, looking up at him in curiosity before the white haired child pulled the dark grey child away, dropping the flowers as they ran.

“Hey! Come back! I won’t hurt you!” Nightmare ran after them, he felt the source of power felt stronger the more he chased the kids.

He soon found the children run up to a tall man in black with eight hands with holes in them floating around the man.

“Hey! What are you doing to-” Nightmare stopped as the man turned, the children hiding behind his legs. He looked like an alternate Gaster. He wore glasses and held a purple monster SOUL in his hands.

“What are you doing to that SOUL?” Nightmare walked closer to the skeleton.

“Nothing!” The skeleton’s feelings spiked up. “W-who are y-“

“What the hell are you doing to that SOUL? What’s with this empty AU? What the hell is with this huge mass of power coming from it?” Nightmare stood directly in front of him.

“Er, who are you? Why do you ask so many questions?”

“Never mind who I am right now. I want to know what you’re doing and why this universe is self-destructing!” Nightmare interrupted.

“This SOUL is my own, stranger. I’m trying to destroy it.” The man blatantly stated.

Nightmare’s eyes widened, “What? Why?”

The skeleton sighed, looking at the SOUL in his hands, “I failed to fulfill what I why I was here, just to create something perfect for these children.” He gestured to the two achromatic kids now behind Nightmare. “Unfortunately, I have no idea _what_ to create. This “talent” of mine shouldn’t belong to me. That’s why I must destroy it.”

“You’re the creator of this world? So much power in the SOUL of yours, but I can sense the sadness and sorrow in you-“

Nightmare was cut off by the man’s hands raised towards him in a threatening way, “THAT IS WHAT I AM, SADNESS AND SORROW! LEAVE MY WORLD BEFORE I HURT YOU STRANGER!” His eyes glowed purple.

Nightmare backed slightly, ready to summon his staff if he had to, “You’re not sorrow and sadness, you are powerful, probably creative, and you may have some good ideas if you try.” He extends an arm out, “What’s your name?”

“W-what’s a ‘name’?” The man asked.

Nightmare was in ever more shock, “Excuse me _what the fuck?_ You don’t know what a name is?!” He walked closer to the man, “Ok, I’m not leaving until you have the motivation to not destroy yourself and create something!”

“But, what makes you think you are able to help me?” The skeleton held his SOUL in his hands.

“Let’s just say I help people like you on an almost daily basis. Just call me Nightmare.” Nightmare grinned.

“Well, if you insist, I guess I don’t have a choice. I guess I’m, myself.” He looks over to the children, “And I guess these are… my kids.”

Nightmare sighed, “Don’t worry, I’ll come up with a name and help you out. Trust me.”

Nightmare spent quite some time in the universe, talking to the guy. It was the first time Nightmare met someone like him. His universe was called X-Tale. He had to admit he was relieved Dream didn’t get to this guy and the kids first.

The skeleton was so upset, he knew nothing of timelines, humans, or monsters. Nightmare tried his hardest to talk to him, but he refused to accept Nightmare’s help.

Nightmare soon pulled out pictures from his “travels”, showing him the different possibilities of different AUs and timelines. He couldn’t create anything like the man could, but he could at least show what he could create.

But he didn’t deem it enough for him. He wanted something more “perfect” to use his capacity for his world.

Nightmare huffed in frustration. This guy was pretty stubborn when it came to inspiration.

“I’m wasting this given power, I continue to fail my children again and again.” He started, “I have no idea what to create, or how to create. Maybe they may be free if I destroy myself with this place…”

Nightmare had enough, “Alright! Hold the fucking phone!” He walked up to the man.

“What even is a ‘phone’?” He held his head as Nightmare walked up to him.

“Listen bud, look at me. You shouldn’t beat yourself or destroy this place for being uninspired or unmotivated.” Nightmare held out his hand. “I have one more ace to help you out. I’m not going to leave you or this place until you won’t destroy this place or yourself. Don’t say no, I won’t allow it.”

He sighed, “You have no way to calm down do you? Alright, let’s see this ‘ace’ of yours.” He took Nightmare’s hand, and Nightmare opened a portal, leading him out of the empty universe to X-Tale’s island base. The cracks Nightmare spotted slowed, barely moving at all.

Before the two, and the children who followed, were the islands of AUs, scattered about like multicolored stars around them.

“This is the rest of the multiverse,” Nightmare started, “Where infinite possibilities and variations of each other exist. Some simple, some complicated. Some sweet, and some where you don’t know what the hell is happening. So many stories exist out here. You could probably create something new that stands out against the rest. Something extraordinary. I’m sure no one else out there has that very ability you hold, creating something out of nothing. You can create whatever you want and make the perfect world you want.” He looked at the taller man, “Why don’t I give you a personal tour? Of course we’ll have to be careful.” He muttered the last part. “So? What do you think?”

The man was silent, in complete awe at the many worlds before them. He then spoke, his words sealing the very fate of his world, and most likely the rest of the multiverse.

_“I would greatly appreciate it, my friend.”_


	2. Our Game

**Summary for the Chapter:**

> XGaster shows introduces his friend to something powerful.

“Hey! Been a while since we last met huh?”

“Oh, T͕̠̺̩m̞̠͔͍̉ͦ̈͗̕l̵̪͖̝̠̹̓́ͥn͙̠̳̦̰̮ͯ̓̄̓͊ͦͅa̛͚̝̞͔͙̱͈ͥ̇ͮ̎͒H̨̪̟̗̜̩͔̓R̹̖̣̭̫͓̋̽̍͞t̹̮̯̦͇ͫ̃̓̅ͤŸ͇̼̫̜́̎̍ͥͩ̍́X̲̘͎̫̐ͣ̄̈͗̓͞J̶̩̫͚̩͎̭̲l̡̺̀ͭ. It’s great to see you again! It has been a while, dear friend.”

“I wanted to see how you were doing with your creations, it’s not common I have time to visit without by brother chasing my ass. Hm, something happened here. Did you or one of the kids RESET? Not sensing any motivation in you.”

“O-oh. Oh no, it was something else. I think I may be a perfectionist, I want to use every speck of potential of my power for a little idea I thought about before.”

“Which power?”

“You, you want to see it? Are you sure?”

“Of course! Like I said, I got time.”

XGaster extended his hand towards his friend, a purple rectangle appearing above his hand. In blocky letters, it spelled OVERWRITE.

“OVERWRITE. This is the power to create anything out of nothing, to completely change one thing to another. It’s reality is itself of an Alternate Universe. It is how I will try to work out my future experiment. Kind of like a game to explore.”

“Change everything? A game?” XGaster’s friend leaned against a tree, “I’m not sure. That doesn’t sound okay…”

“I know you’re one for balance of the multiverse, after what your brother did. But please understand, I want the best for my children.” They both looked over to XFrisk and XChara, “It has been my dream to create something like this, and thanks to you, I have the perseverance I’ve been missing.” He looked back up at his friend. “I just need the right timeline to execute the game.”

“The both of us could play anytime, anywhere. We can have fun with it I’m sure. It can be the best thing you may have ever seen.”

His friend looked back up at XGaster, uncertainty painted on his face, “Well, I’m still uncertain about this ‘game’ of yours,”

“Before you say anything else, let me tell you that this game, a game for a perfect multiverse, could bring back the balance your brother destroyed so long ago. You could have your brother back.”

The last question surprised his friend into thought, making him silent for a moment.

“Well? What do you say?”

“I’m still not totally on board with your plan, I just hope this game won’t go too out of hand.”

XGaster smiled at his response, “So you’re on board with my game?”

“Call it _our_ game, I’ll be waiting when you find the perfect timeline.”

“Glad you decided to come around, T͕̠̺̩m̞̠͔͍̉ͦ̈͗̕l̵̪͖̝̠̹̓́ͥn͙̠̳̦̰̮ͯ̓̄̓͊ͦͅa̛͚̝̞͔͙̱͈ͥ̇ͮ̎͒H̨̪̟̗̜̩͔̓R̹̖̣̭̫͓̋̽̍͞t̹̮̯̦͇ͫ̃̓̅ͤŸ͇̼̫̜́̎̍ͥͩ̍́X̲̘͎̫̐ͣ̄̈͗̓͞J̶̩̫͚̩͎̭̲l̡̺̀ͭ.”


End file.
